This study proposes to test the effectiveness of a hydration management guideline to prevent acute confusion in residents of long term care. While acute confusion/delirium is a complex health care problem for the elderly, with dire consequences if left untreated, few intervention studies have been conducted to prevent acute confusion in any setting. In fact, much of the research conducted to date has sought to describe the phenomenon in acutely ill hospitalized elders, but no nursing interventions have ever been tested in long term care. The few intervention studies conducted in acute care settings have reported clinically ambiguous or insignificant results and none have focused on a single etiologically based condition, such as dehydration. While there are other precipitants which lead to acute confusion, dehydration negatively influences many of these other precipitants, such as urinary tract infection, drug metabolite accumulation, respiratory infection, blood volume deficits and resulting cerebral hypoperfusion. Further, dehydration is the precipitant most amenable to nursing intervention. Therefore, the specific aims of this study are to (1) test the direct effect of a hydration management guideline on the incidence of acute confusion, and (2) test the indirect effect of hydration management guidelines on incidence of urinary tract infection in the long term care setting. A treatment-control group design will be used to test the effectiveness of a three month individualized fluid intake regimen based on weight with 160 elderly long term care residents over two consecutive years. Using the presence or absence of confusion as a dichotomous outcome, a projected 20% drop in incidence as a result of the hydration intervention, and 80% power, a total of 80 subjects will be required in each of the treatment and control groups (N=160). Two Iowa Veterans Affairs facilities and two comparable community sites will be used as the research setting with stratified random sampling by gender to ensure gender balance for the study. A two month follow-up of the treatment group to evaluate the feasibility of staff maintaining the intervention guidelines without research support will be conducted. Survival analysis techniques will be used to analyze the data with Kaplan Meier probability curves.